Scientific narratives are pervasive in international policy, in part, due to the increasing degree to which technological considerations enter modern thinking. These narratives are particularly visible in the chemical weapon prevention regime, which must accommodate changes in science and technology to ensure that they do not result in the application of new utilities for toxic chemicals as weapons. The dissertation investigates the function of technical experts, and the perceptions of their role, in the procedures of the chemical weapon prevention regime that address technical change. It explores expert involvement in three elements of the Chemical Weapons Convention (CWC): its negotiation; the Scientific Advisory Board; and in national policy formulation. Ethnography – from an extended placement within the Convention's monitoring body, the Organisation for the Prohibition of Chemical Weapons (OPCW) – as well as interviews and documentary sources provide the methodological basis for the research. The dissertation finds that science is often made political within the international policy setting, and shows how science is employed to support political aims whether it is in accelerating or slowing policy formulation, or in deflecting the policy agenda. It argues that whilst the role of experts and their capacity to influence policy vary with the forums in which they are placed, their effectiveness depends also upon other factors, including institutional support. The dissertation also holds that national approaches to expert advice are reflected in state relationships with experts advising at the international level. The research supports much of the Science and Technology Studies (STS) literature on experts in national settings and has substantial implications for a concept popular in International Relations (IR) literature, namely, ‘epistemic communities'. A case for reframing ‘epistemic communities' is developed which incorporates notions drawn from STS, such as the important role of ‘boundary organisations'. These are applied to the CWC, and policy recommendations for the OPCW and its member states are presented.

Disposal of low level radioactive liquid waste to soil is commonly practiced. Therefore, sorption of uranium from aqueous solution and fixation of uranium into soil are processes which are crucial to the attenuation of uranium and protection of groundwater. Exposure of human populations is either by direct water consumption or through crop irrigation and transfer into the food chain. In this study a range of materials, including natural materials (e.g. biochar and the natural zeolites ‘Chabazite and Mordenite’) and the synthetic zeolite ‘Faujasite-X’, were investigated as potential adsorbents for UVI from aqueous solution. A range of experiments were carried out to investigate the efficacy of using these adsorbents to successfully adsorb and fix UVI from aqueous solutions. These included sorption and desorption experiments, quantifying time-dependent fixation of UVI and applying kinetic models of this process and measuring isotopically exchangeable UVI within adsorbent materials when possible. The factors affecting adsorption processes, such as solution pH, initially added UVI concentrations and adsorption contact time, were also investigated. Speciation of U in the solution phase was investigated using the Windermere Humic Aqueous Model (WHAM-VII). Saturation indices of potential solid phases were also configured using known solubility products and the free ion activities predicted from the speciation model, WHAM-VII. Mordenite zeolite showed a poor adsorption affinity for UVI as the solution pH was continuously buffered towards high pH values > 6.5 which favours UVI ion solubilisation as a result of uranyl carbonate complex formation. Uranium (VI) ion adsorption on chabazite at pH 4.7 at 20 oC was found to fit the Freundlich adsorption isotherm but the optimised equation parameters were unique for each contact time of 1, 5, 10, 20 and 30 days. The time-dependent fixation of UVI on chabazite was found to follow an irreversible first-order kinetic equation and an intraparticle diffusion model suggesting slow penetration of chabazite porous structure following initial surface adsorption. Isotopically exchangeable 238UVI (the E-value, UE) adsorbed on chabazite showed that > 65% of initially added UVI remained isotopically exchangeable. Faujasite-X also showed time-dependent fixation of UVI over 35 days of adsorption contact time at pH values 4, 5 and 6. The adsorption kinetics were best described by an irreversible first-order equation and a spherical diffusion model. Desorption trends showed that UVI adsorption into faujasite- X was almost wholly irreversible. Saturation indices calculated from the solubility products and free ion activities of constituent ions showed that the fixation of UVI was not controlled by the precipitation of any solid phase investigated at the studied range of pH values. Bone biochar, a by-product from the production of biofuel and syngas by gasification, was tested as a material for adsorption and fixation of UVI from aqueous solutions. A batch experiment was conducted to study the factors that influence the adsorption and time-dependent fixation on biochar at 20◦C, including pH, initial concentration of UVI and contact time. Uranium (UVI) adsorption was highly dependent on pH. However, it was found that UVI adsorption on biochar was high over a wide range of pH values, from 4.5 to 9.0, and adsorption strength was time-dependent over several days. The experimental data for pH> 7 were most effectively modelled using a Freundlich adsorption isotherm coupled to a reversible first order kinetic equation to describe the time-dependent fixation of UVI within the biochar structure. Desorption experiments showed that UVI was only sparingly desorbable from the biochar with time and isotopic dilution with 233UVI confirmed the low, and time-dependent, lability of adsorbed 238UVI. Below pH 7 the adsorption isotherm trend suggested that precipitation, rather than true adsorption, may occur. Across all pH values (4.5–9) measured saturation indices suggested precipitation was possible: autunite below pH 6.5 and swartzite, liebigite or bayleyite above pH 6.5 Another source of bone biochar with a fraction size of (20x 60 mesh) was investigated as candidate materials for soil remediation. Its ability both to adsorb uranium and to render it non-labile (i.e. chemically inactive) was tested by addition to a wide range of soils recently spiked with 238UVI and incubated under moist conditions. The overall aim was to recommend improved strategies for immobilisation of uranium in soils subject to application of low level radioactive waste solutions. Several measurements were made to assess possible reductions in U availability from biochar addition, including U solubility in 0.01 M Ca(NO3)2, exchangeability in 1 M Mg(NO3)2 solution and isotopic dilution with 233U and 236U. Results showed that 41.3 %, 27.6%, 28.9% and 31.7% were isotopically exchangeable on average for soil amended with 0%, 3%, 5% and 10% loading of biochar, but overall there appeared to be only marginal advantages in adding even large concentrations of biochar to soil. The major factor controlling U solubility, exchangeability and lability was soil pH and the pH value resulting from biochar, rather than the biochar itself. Therefore, while the use of biochar to effectively remove U from water is clear, its role in adsorbing U in the highly buffered soil environment is probably minimal.

Mesophilic anaerobic digestion is one of the most used and successful technologies to treat the sludges resulting from wastewater treatment. However, traditional approaches to digester design are firmly rooted in empiricism and rule of thumb rather than science. Mixing is an energy-intensive operation, and therefore the need to lower the wastewater process carbon footprint requires searching how to lower the input mixing energy without compromising–and indeed enhancing–biogas production. In particular, the literature on gas mixing is still particularly poor. For the first time, an Euler-Lagrangian CFD model was developed for gas mixing in anaerobic digestion. The model was validated against laboratory experiments with PIV and PEPT techniques. Full-scale simulations reproducing a real digester were performed with the validated model, and different scenarios were reproduced. Shear rate distribution was used as a parameter to assess the most appropriate value of input mixing power. The simulations also low-viscosity flow patterns for the first time. This phenomenon is intrinsically linked to the non-Newtonian nature of sludge, and leads to short-circuited mixing. Switching biogas injection between two different nozzle series was found to be an effective strategy to mitigate the issue of the low-viscosity flow patterns. Final recommendations on input mixing power and switching time were given to improve mixing efficiency in the full-scale design taken into consideration. A journal paper published in Water Research and a conference paper presented at the Fifteenth International Conference on Civil, Structural and Environmental Engineering Computing (Civil-Comp) were produced. Two other papers are currently in preparation.

The recovery of metals from secondary resources is increasing to alleviate supply risks associated with primary sources. Thermal plasma is widely used for platinum group metal recovery from automotive catalysts, but the mixing of various catalyst types makes their processing difficult. It was found that it was possible to separate silicon carbide based catalysts from cordierite based catalysts by a combination of magnetic and electrostatic separation processes resulting in a cordierite fraction of over 98 % purity, which would result in a more consistent feed material to the plasma process enhancing metal recovery. The flexibility of plasma means that the operational conditions in the furnace can be controlled to suit the chemistry of less noble metals such as rhenium and drive gas phase reactions. The technology was used to recover platinum and rhenium from spent petrochemical catalysts via a novel pyrometallurgical process with over 98 % recovery efficiencies of both metals. The plasma process produces a large amount of slag as a by-product which can be used in higher value applications to avoid waste and improve business models. Plasma derived slag was shown to be an effective, low carbon cement replacement which can potentially obtain a market value of £50/tonne.

Experimental results and analyses have shown that significant improvements in coal grindability (reductions in Relative Work Index) can be achieved by exposing coals to microwave radiation. Experimental data have indicated that low rank coals are highly responsive to microwave radiation, possibly due to their higher inherent moisture content. There is evidence to suggest that gaseous evolution (water vapour and volatile matter) and localised zones of differential expansion (arising for example from occluded mineral matter) in coal during heating give rise to crack formation and hence are the probable causes for the measured increase in coal grindability. The composition of the various coals treated by microwave radiation remained relatively unaltered and there was no significant change in coal calorific value or the proximate and ultimate analyses (dry, mineral matter free basis). Initial (laboratory-scale) microwave trials and pilot-scale testwork demonstrated an improvement in the grindability of various coals. However, the gross energy input for these tests were excessively high (220k WhIt) in comparison to that used mechanically for pulverised coal production (15-20kWhlt). Improvements in microwave cavity design and increased electric field strengths may increase the energy efficiency of the process; however, further work would be required. Additional studies were carried out to evaluate the potential use of microwave technology for coal desulphurisation. The results were encouraging and show that substantial improvements in pyrite separation can be achieved with some coals. Fundamental studies have shown that there is significant change in coal flowability following microwave exposure.

In this thesis, biological and imaging studies have been carried out on a supramolecular helicate (iron cylinder) and indirect methods to image this non-fluorescent compound have been developed. The iron cylinder has been investigated as a quencher of nuclear Hoechst fluorescence in a range of cancer cell lines. Flow cytometry and epifluorescence data has shown quenching occurring in a concentration-dependent manner at both the population and cellular level. These results provide evidence for the cylinder being able to interact in close proximity to the DNA within 20 minutes of administration. Using luciferase-expressing breast cancer cells, the iron cylinder has been shown to directly affect light emission in a concentration-dependent manner, an inhibition that has not previously been investigated providing further opportunities for imaging by monitoring the inhibition of luminescent enzymes. Furthermore, iron cylinder has been shown to quench GFP fluorescence using fluorimetry and confocal microscopy providing novel possibilities supporting the imaging of non-fluorescent compounds indirectly through the use of fluorescent stains. This thesis has also pioneered the first in vivo research relating to the iron cylinder in the model organism, zebrafish, and findings indicate a large therapeutic window over which the cylinder can bring about its effects.

Highly conductive (3.0 - 5.0 x 10 \(^{-4}\) \( \Omega\) cm) and transparent (80 – 85% ) ITO films were successfully fabricated on glass and polymer substrates (PET, PEN and PC) by pulsed laser deposition at low temperatures (24 – 150 °C). The influence of deposition conditions on the structural and physical properties of ITO-coated glass substrates was studied. The samples were investigated using Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), X-Ray Diffraction (XRD), the fourpoint probe and a spectrophotometer. Sol-gel derived ITO films dip-coated on glass substrates were also studied. The optimum film obtained at a firing temperature of 600 °C had a resistivity of 1.8 x 10 \(^{-2}\) \( \Omega\) cm, and optical transmittance of 80%. The electro-mechanical behaviour of ITO/polymer systems was investigated under uniaxial tension and controlled buckling in tension and compression. The resistance changes were monitored in situ. Cracking and buckling delamination failure modes were observed for all samples investigated at critical strains raging from 2.8 to 3.4%, and from 7.0 to 8.0%, respectively. The results showed that the dominant critical failure mode depends on the applied stress conditions. The ITO/PEN samples showed high flexibility; the samples were buckled in tension down to a 2.6 mm radius of curvature before cracks start to occur.

Conservators treat and repair a huge array of damaged and degrading materials on a regular basis. As such, there are many techniques and protocols in place to deal with these problems successfully, be that via preventative or interventive methods. However, there is need for new and innovative techniques that offer long term stabilisation to materials and objects that are prevalent within museum collections. As an alternative to some of these conservation techniques, hydration with supercritical carbon dioxide was investigated here. Both modern and historic, hardwood and softwood samples were successfully hydrated using this technique. The addition of a co-solvent (methanol) to the supercritical fluid solvent stream was used as a method to increase the solubility of water in carbon dioxide, and therefore improve levels of hydration. To evaluate the extent of any damage being caused during the supercritical fluid treatment, microstructural and macrostructural analytical techniques were carried out. The supercritical hydration technique allowed historic wood to be hydrated and stabilised. Strength properties were seen to be maintained or improved after the supercritical treatment, providing conservators with a viable method of hydration. A feasibility study looking at the cleaning and characterisation of historic leather samples was investigated using spectroscopic methods. The sensitivity of Diffuse Reflectance Infrared Fourier Transform spectroscopy on historic leather was explored. Additionally, changes in elemental composition on the surface of the leather were monitored using Scanning Electron Microscopy Energy Dispersive spectroscopy. Cleaning historic leather via a supercritical carbon dioxide solvent stream showed the greatest potential for future work. However, the characterisation of unattributed historic leather is a vast and complex task that would require the expertise of a leather conservator, if the investigation were to be continued.

The ageing of Solid Oxide Fuel Cells (SOFCs) is a key problem because of the requirement of 50,000 hours to their lifetime in many applications. At present, such performance is still not attainable because degradation occurs at more than 1% per thousand hours under practical test conditions. In this thesis, the ageing of the Rolls Royce Fuel Cell Systems (RRFCS)Integrated Planar Solid Oxide Fuel Cell (IP-SOFC) was studied under different operating conditions, especially by accelerated degradation testing (ADT), in order to investigate the fuel cell stability and degradation behaviour under non-steady operating conditions for further improvement of the systems. This work demonstrates that the long-term durability of the IP-SOFC is very good when pure hydrogen is used as fuel. However, the introducing of even a small amount of methane in fuel has demonstrated the capacity to damage the IP-SOFC through the formation of carbon deposits on the anode surface. Future work is therefore required to identify viable alternative materials and optimal operating conditions.

Adsorption of heavy metal ions (e.g. copper, nickel and lead) onto sphagnum moss peat was investigated. The influence of pH, concentration, temperature, nature of solute, number of solutes simultaneously present, peat dose and reaction time on batch adsorption equilibria and kinetics tests were examined. Batch adsorption of copper and nickel onto peat was pH dependent, the optimum range being 4.0 to 5.0 for copper and 4.0 to 7.0 for nickel. Langmuir and Freundlich isotherms showed a single relationship between initial metal concentration, metal removal, and initial pH. The latter was found to control efficiency of metal removal. The use of peat in removal of lead from aqueous solution was studied in batch experiments. Investigations included the effect of pH and temperature of adsorption. The adsorption equilibria data followed Langmuir and Freundlich models. Efficiency of lead removal depended very little on the reaction temperatures (12 to 37°C) and initial pH values (4.0 to 6.0). The results suggested that the adsorption process is endothermic for lead-peat adsorption. Kinetic data suggested involvement of a chemical rate-limiting step, and a predictive relationship was derived relating metal removal to peat dose. In comparison with other metals, nickel removal is poor, and possible reasons are discussed. Kinetic results also indicated that pore diffusion is not the only rate determining step in peat metal adsorption. A rate equation is described for the study of the kinetics of adsorption of aqueous divalent metal ions onto sphagnum moss peat for a range of conditions. An empirical model was devised for predicting percentage metal ion adsorbed. The model showed a high coefficient of correlation, indicating its reasonableness. The last section describes the results of an examination into the simultaneous adsorption by peat of several metals. Initially copper and nickel from both single- and bi-solute systems were tested. In general, pore diffusion appeared to be the rate-controlling step. The effects of competitive adsorption in batch systems for copper and nickel system was also studied in various ratios of metal concentration. A mathematical model was used successfully and shown to be predictive for various ratio of metal ions concentration in competitive adsorption. The dose effect on the uptake of metals on moss peat was also studied for bi-solute adsorption systems. The best interpretation which could be placed on the data was that the behaviour of nickel was unusual. The results also showed that the kinetics of adsorption were best described by a second-order expression rather than a first-order model. For metal ions which are of different size but are divalent metal ions, we used lead(II) and copper(II) as well as lead(II) and nickel(II) systems. The effects of competitive adsorption in batch systems indicated that copper had a greater effect on lead adsorption than did nickel. However, lead had a greater effect on nickel than copper. A copper, lead and nickel triple-solute system was also tested. The adsorption of any single metal such as copper, lead and nickel was hindered by the presence of the other metals. The competitive effect appears to have affected the three ions in the order nickel > lead > copper with nickel affected most; the adsorption capacity for each solute from the mixed solution was 15.9, 57.4 and 71.5% of that of a single-solute system for copper, lead and nickel, respectively. The kinetic results showed that the heavy metals are adsorbed fairly rapidly, and that there is a relatively good fit between experimental data and the second order model for copper, lead and nickel.